Polyalkanolamine condensed with fatty acid mixture



Patented Jan. 23, 1951 POLYALKANOLAMINE CONDENSED WITH FATTY ACIDMIXTURE George Zinzalian, Boontoi i, N. 1., assignor to E. F. Drew &00., Inc., New York. N. Y., a corporation of Delaware No Drawing.Application April 23, 1946,

Serial No. 664,431

7 claim? (Cl. 260-404) The present invention is directed to condensationproducts, more particularly to such pi'oducts formed by the reactionbetween fatty acids and certain amines. Products of this type haveexcellent wetting properties.

It has heretofore been proposed to react a fatty acid or a mixture offatty acids, usually obtained from vegetable or similar oils, withalkylol amines. Reaction products of this type were produced by reacting2 mols. of the alkylol aminewith 1 mol. of the fatty acid. It wascustomary in such procedures to provide a mixture of the reactants andheat the same to a temperature as high as 300 C. to cause a. reaction totake place therebetween. The resulting products were wetting agents andhave found considerable use in industry. As the acid constituent andsuch substances. single higher fatty acids were used, such as stearlcacid or certain mixtures of fatty acids were employed, such as the mixedfatty acids obtained by the hydrolysis of cocoanut oil.

One of the important uses for substances of this type has been as awetting and cleansing agent for personal use. Solutions of thesesubstances in water have been on the market as hair shampoos and asbubble bath solutions. While substances made in accordance with theprior art were applicable for such uses. they suffered from severaldisadvantages. For instance, there was a tendency for crystals to beprecipitated if the solutions were kept in a cold place, such as 40 to45 F. for a substantial time. After such precipitation, it was difficultby heating t e solution to bring the crystall ne materal back intosolution. This rendered the product unusable in many instances. Also,the suds ng power of the material was not entirelv satisfactory.Furthermore, no direct and adequate control of the reaction process wasattempted so that various batches of the same reaction product haddifferent wetting properties and different solubilities in water.

The present invention is intended and adapted to overcome the dimcnltiesand di advantages inherent in the prior art and to provide a method ofproducing condensation products of the type above set forth, it be ngamon the obects of the present invention to provide an adequate controlfor the operation wh ch will insure uniform and reproducible results.

It is also among the ob ects of the present inform wetting power andwhich is completely soluble in water.

It is further among the objects of the present invention to provide aproduct of the type described which will form clear solutions in greatdilutions, which will remain clear without depositing any crystallinematerial, and which will produce optimum sudsing power in use.

In practicing the present invention, an alkylol amine is heated to apoint above its melting point and while at such temperature, there isadded thereto a mixture of fatty acids. The proportion is about 2 mols.of alkylol amine to 1 mol. of said fatty acids. The fatty acid usedconsists of amixture in which the principal acid is lauric acid withminor amounts of caprlc and myristic acids.

In the reaction the mixture so formed is heated slowly and gradually fora period of several hours until a temperature of about to C. is reached.Then the temperature is held at said maximum for several hours until thereaction has gone to the desired extent. During the reaction. water isformed which preferably is removed at such rate so as to prevent theformation of substantial amounts of foam. It is advisable that some ofthe condensed water be returned to the reaction. 1

The reaction is arrested when the free fatty acid content is below 15%of the total acids present in the reaction mixture. It is es ent al thatsome free fattv acid remain in the mixture and usually at least 1% ofsuch acid remains. If the reaction is arrested at th s point, then thecondensation product is completely soluble in water and forms clearsolutions when present in amounts from .1% to 10% of the solution. Ithas a high wetting speed and meets the standard sudsing test. Instanding at low temperatures. no insoluble matter is formed and thesolution remains clear.

The proportions of the fatty acid present in the reaction mixture areimportant and fall within the following limits.

Percent Lauric Acid 80-95 Capric Acid 4-10 Myristic Acid 1-10 It hasbeen found that within such limits,

wherein the lauric acid is by far the major const tuent and the otheracidsare present in minor amounts, the desirable pro erties of thecondensation product are obtained. The alkylol amines used arepreferably the dior tri-polyalkylol arcane Myristic a 2 There is alsoprovided diethanol amine, which is placed in the reaction kettle andheated to between 50 and 70 C. in order to melt the diethanol amine.There is then added to the melted diethanol amine the above mixture offatty acids, and the mixture is agitated during the addition of theacid, the temperature rising gradually to about 90 C. The ratio of theconstituents in the reaction vessel is about 5100 lbs. of diethanolamine and 4900 lbs. of the mixed fatty acids. The kettle is heated tocause a slow and gradual rise in temperature, the rate of heating beingsuch that a temperature of about 150 C. is reached after heating forabout four hours. Heating is continued to maintain the temperature atabout 150 C. for about three additional hours. By this time, theapparent free fatty acid content of the reaction mass is less than 15.Heating is then discontinued and the reaction is considered to becomplete.

The completion of the reaction may be gauged by testing the reactionmixture from time to time. A solution of .1% of the condensation inwater is crystal clear. When 50 cc. of this solution is placed in a 4ounce oil sample bottle and vigorously shaken ten times, it developsfrom one and one-half to two inches of foam. Said solution whensubjected to the Draves test shows a wetting speed of seconds or less at25 C.

The reaction product is capable of dilution with water to an extremelylow concentration without producing cloudiness. It has a high sudsingpower and has excellent wetting and cleansing properties. The procedurecan be repeated time after time with the resulting condensation producthaving uniform and highly desirable wetting and cleansing properties.The control of the operation is relatively simple and no difflcultiesdevelop in carrying out and in repeating the procedure.

Although the invention has been described setting forth a singlespecific embodiment thereof, said specific example is intended toillustrate the invention and not to limit the same. Various changes inthe details of the procedure may be made without departing from thespirit of the invention. For instance, although in the first step of theoperation the alkylol amine is heated to above the melting pointthereof, before the addition of the fatty acid mixture, it is possibleto heat the same to a temperature higher than that set forth in thespecific example, but below the principal reaction temperature, say upto 90 or 100 C. before the addition of the fatty acid mixture. The waterformed in the reaction may be removed continuously by subjecting thereaction kettle to a partial vacuum whereby most of the water is removedduring the reaction. It is desirable that the water be removed but thepresence of some water in the reaction mixture is not detrimental. Theremoval of the excess water may be accomplished by different methodsthan the above mentioned vacuum.

. 90 10 Capric acid 8 The course of the reaction is dependent upon boththe temperature and the time involved. When the higher temperatures areused, the reaction proceeds more vigorously and therefore the time ofreaction is correspondingly decreased. Also when a vacuum is used duringthe reaction, the same is accelerated and this may be compensated for byeither reducing the time of reaction or lowering the temperaturethereof, or both. In place of the acids specifically set forth, otherfatty acids having the some numbers of carbon atoms, which may beconsidered isomeric with the acids named herein, may be used in placethereof, either in whole or in part. The mixture of fatty acids isessential to the operation as the properties obtained in the eventualcondensation product are believed to have the desirable properties dueto the mixed compounds produced.

These and other changes in the details of the invention may be madewithin the scope thereof and the invention is therefore to be broadlyconstrued and not to be limited except by the character of the claimsappended hereto.

I claim:

1. A condensation product of about 2 mols. of a polyalkylolamine havingfrom 2 to 3 carbon atoms in the alkyl groups with about 1 mol. of amixture of lauric, capric and myristic acids, the lauric acidconstituting at least of the acids present, said product having a freefatty acid content of 1% to 15% of the total acid present formed byheating the reaction mixture to gradually raise the temperature to about-155 C. and maintaining said temperature until the free fatty acids are1% to 15% of the acids present.

2. A condensation product of about 2 mols. of a polyalkylolamine havingfrom 2 to 3 carbon atoms in the alkyl groups with about 1 mol. of amixture of lauric, capric and myristic acids in the followingproportions:

' Percent Lauric acid 80-95 Capric acid 4-10 Myristic acid 1-10 having afree fatty acid content of 1% to 15% of the total acids present formedby heating the reaction mixture to gradually raise the temperature toabout 140-155 C. and maintaining said temperature until the free fattyacids are 1% to 15% of the acids present.

3. A condensation product of about 2 mols. of diethanolamine with about1 mol. of a mixture of lauric, capric and myristic acids, the lauricacid constituting at least 80% of the acids present, said product havinga free fatty acid content of 1% to 15% of the total acid present formedby heating the reaction mixture to gradually raise the temperature toabout 140-155 C. and maintaining said temperature until the free fattyacids are 1% to 15% of the acids present.

4. A method of making condensation products which comprises heating 2mols. of a polyalkylolamine having from 2 to 3 carbon atoms in the alkylgroups to above the melting point thereof, mixing therewith at saidpoint about 1 mol. of a mixture of lauric, capric and myristic acids ofwhich lauric acid constitutes at least 80% of the acids present, heatingthe reaction mixture to gradually raise the temperature to about 140-1550., and maintaining said temperature until the free fatty acidsremaining in the condensation product are 1 to 15% of the acids present.

5. A method of making condensation products which comprises heating 2mols. of a polyalkylolamine having from 2 to 3 carbon atoms in the alkylgroups to above the melting point thereof, mixing therewith at saidpoint about 1 mol. of a mixture of lauric, capric and myristic acids ofwhich lauric acid constitutes at least 80% of the acids present, heatingthe reaction mixture to gradually raise the temperature to about 140-155C., and maintaining said temperature until the free fatty acidsremaining in the condensation product are 1 to 15% of the acids present,while removing in the vapor state water formed in the reaction.

6. A method of making condensation products which comprises heating 2mols. of diethanolamine to above the melting point thereof, mixingtherewith at said point about 1 mol. of a mixture of lauric, capric andmvristic acids of which lauric acid constitutes at least 80% of theacids present, heating the reaction mixture to gradually raise thetemperature to about 140-155 C., and maintaining said temperature untilthe free fatty acids remaining in the condensation product are 1 to 15%of the acids present.

7. A method of making condensation products which comprises heating 2mols. of a polyalkylol- -6 amine having from 2 to 3 carbon atoms in thealkyl groups to above the melting point thereof, mixing therewith atsaid point about 1 mol. of a mixture of lauric, capric and myristicacids of which lauric acid constitutes at least of the acids present,heating the reaction mixture to gradually raise the temperature to about1 4'0-155 C., and maintaining said temperature until the free fattyacids remaining in the condensation product are 1 to 15% of the acidspresent, while removing in the vapor state water formed in the reaction,and returning a part of the water to the reaction.

GEORGE ZINZAL IAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,089,212 Kritchevsky Aug. 10,1937 2,173,448 Katzman et a1 Sept. 19, 1939 2,173,909 Kritchevsky Sept.26, 1939 2,334,852 Weisberg et al Nov. 23, 1943 2,388,281 Orelup Nov. 6,1945

1. A CONDENSATION PRODUCT OF ABOUT 2 MOLS. OF A POLYALKYLOLAMINE HAVINGFROM 2 TO 3 CARBON ATOMS IN THE ALKYL GROUPS WITH ABOUT 1 MOL. OF AMIXTURE OF LAURIC CAPRIC AND MYRISTIC ACIDS, THE LAURIC ACIDCONSTITUTING AT LEAST 80* OF THE ACID PRESENT, SAID PRODUCT HAVING AFREE FATTY ACID CONTENT OF 1% TO 15% OF THE TOTAL ACID PRESENT FORMED BYHEATING THE REACTION MIXTURE TO GRADUALLY RAISE THE TEMPERATURE TO ABOUT140*-155* C. AND MAINTAINING SAID TEMPERATURE UNTIL THE FREE FATTY ACIDSARE 1% TO 15% OF THE ACIDS PRESENT.